IBM offers a set of icons and also a set of pictograms. In this way they can classify both in different ways. The pictograms are more detailed and used for illustrative purposes. 👏🏻
— Source (Carbon Design System)
— Diana Mounter, GitHub / Source (YouTube)
Increments of 4px (0.25rem) for spacing, line heights, …
»This allows us to avoid the need for a variables like medium or large. There you get into a system where you have to memorize the naming conventions for your variables. We’re replacing that with a simple rule you need to remember.«